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DR. LOUISE ARONSON M.D.
NPI 1780786772
Internal Medicine - Geriatric Medicine in San Francisco, CA

Active since September 01, 2006PECOS Enrolled
75/100
CMS Quality Rating
3333 CALIFORNIA ST STE 380 BOX 1265, SAN FRANCISCO, CA 94143(415) 514-3577(415) 514-0702 Get Directions Write a Review

NPPES record last updated: September 11, 2025. Verified against the NPPES registry weekly; last sync: October 25, 2026.

About Dr. Louise Aronson M.d. NPPES

Official registry information on file with the National Plan and Provider Enumeration System.

DR. LOUISE ARONSON M.D. (NPI 1780786772) is an individual geriatric medicine provider in San Francisco, California, licensed in California (G78498) and active in the NPI registry since September 2006. She is enrolled in Medicare PECOS.

NPPES Registry Identity

NPI1780786772
Entity TypeIndividualFemale
Primary Taxonomy207RG0300X
Provider Legal NameDR. LOUISE ARONSONCredential: M.D.
Location Address3333 CALIFORNIA ST STE 380 BOX 1265San Francisco, CA 94143-0001
Mailing Address1635 Divisadero St, Suite 625, Box 1821San Francisco, CA 94143-0001 · (415) 476-4029 · Fax (415) 476-4150
Phone(415) 514-3577
Fax(415) 514-0702
Sole ProprietorNo
Enumeration DateSeptember 1, 2006
Last NPPES UpdateSeptember 11, 2025
✔ NPI 1780786772 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses 2

★ Primary SpecialtyInternal Medicine · Geriatric MedicineAllopathic & Osteopathic Physicians
Taxonomy Code207RG0300X
License✔ Licensed in CA · G78498
Definition
An internist who has special knowledge of the aging process and special skills in the diagnostic, therapeutic, preventive and rehabilitative aspects of illness in the elderly. This specialist cares for geriatric patients in the patient's home, the office, long-term care settings such as nursing homes and the hospital.
Also ListedInternal MedicineTaxonomy 207R00000X · License G78498 (CA)

Other Identifiers 1

Medicaid00G784980CA

Medicare Participation & PECOS CMS

Medicare enrollment, assignment, billing reassignment, and ordering and referring status from CMS.

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

Dr. Louise Aronson M.d. is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).

Eligible to Order & Refer✔ Part B Labs & Imaging✔ Durable Medical Equipment✔ Home Health Agency✔ Power Mobility DevicesPer the CMS Ordering and Referring file. Eligibility means Medicare pays claims that this provider orders or refers for these categories.

Medicare Billing Reassignments

4

Medicare enrollment records show Louise Aronson reassigns Medicare billing to 4 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.

Regents Of The University Of California
Endocrinology, Diabetes & Metabolism
1600 DIVISADERO ST
San Francisco, CA 94143
  • Reassigned Medicare billing, California enrollment
  • 2,112 clinicians in this Medicare group
NPI 1235322348 (415) 353-9720
Ucsf Medical Group Business Services
Internal Medicine
400 PARNASSUS AVE
San Francisco, CA 94122
  • Reassigned Medicare billing, California enrollment
  • 5,544 clinicians in this Medicare group
NPI 1477624104 (415) 353-2808
University Of California San Francisco
Internal Medicine
400 PARNASSUS AVE
San Francisco, CA 94143
  • Reassigned Medicare billing, California enrollment
  • 5,645 clinicians in this Medicare group
NPI 1164512851 (415) 476-1000
University Of California Sfgh Medical Group
Hospice and Palliative Medicine
1001 POTRERO AVE, RM. 5H22
San Francisco, CA 94110
  • Reassigned Medicare billing, California enrollment
  • 637 clinicians in this Medicare group
NPI 1073836060 (415) 206-8317

Source: CMS Revalidation Reassignment List, October 2026 release. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

Areas of Expertise CMS Part B claims

Services this provider delivered to Medicare fee-for-service patients, from the CMS Medicare utilization data. Higher counts generally reflect more experience with a service; care delivered outside Medicare is not included.

Established patient office or other outpatient visit with high level of medical decision making, if using time, 40 minutes or more 99215
This service involves a follow-up appointment for existing patients, lasting between 40 to 54 minutes. During this time, your healthcare provider will assess your current health status, discuss any changes or concerns, review your treatment plan, and answer any questions you may have.
30 services27 patients

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 94143 ZIP code area, from fee-for-service claims. These are area statistics, not this provider’s prices; actual charges vary by service and coverage.

New Patient
$202.35 typical visit price
range $69.00 – $202.35
Typical copayment $50.58 (range $17.25 – $50.58)
Most-billed visit code 99205
Established Patient
$119.48 typical visit price
range $23.44 – $166.46
Typical copayment $29.87 (range $5.86 – $41.61)
Most-billed visit code 99214
Amounts reflect what Medicare beneficiaries in this ZIP area are typically charged for office visits. Patients with other coverage should check their individual plans.

Medicare Quality Performance CMS QPP · MIPS

Performance in the CMS Quality Payment Program: the MIPS final score across four weighted categories, and the individual quality measures reported to Medicare.

75/100
MIPS Final ScoreMerit-based Incentive Payment System · CMS Quality Payment Program
Scored as part of a group practice

Frequently Asked Questions NPPES & CMS

Common questions about this NPI record, answered from the official NPPES registry and CMS datasets shown on this page.

What is Louise Aronson's NPI number?

The NPI number for Louise Aronson is 1780786772. It was assigned to this individual provider in the NPPES registry on September 1, 2006.

Where is Louise Aronson located?

Louise Aronson practices at 3333 California St Ste 380 Box 1265, San Francisco, CA 94143. The listed phone number is (415) 514-3577.

What is Louise Aronson's specialty?

The primary specialty registered for this NPI is Internal Medicine, specializing in Geriatric Medicine, with taxonomy code 207RG0300X.

Is Louise Aronson enrolled in Medicare?

Yes. Louise Aronson is registered in the Medicare PECOS enrollment system.

Which organizations bill Medicare for Louise Aronson's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Louise Aronson reassigns Medicare benefits to 4 organizations: Regents Of The University Of California (San Francisco, CA), Ucsf Medical Group Business Services (San Francisco, CA), University Of California San Francisco (San Francisco, CA) and University Of California Sfgh Medical Group (San Francisco, CA). Each reassignment is filed with Medicare on form CMS-855R, signed by both the clinician and the organization, and lets the organization bill Medicare and receive payment for Louise Aronson's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.

When was this NPI record last updated?

The NPPES record for Louise Aronson was last updated on September 11, 2025. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 13 months ago. If this record has changed at CMS more recently, you can request an on-demand re-check against the live CMS registry, directly from this page.